Synergistic coupling of NiTe nanoarrays with NiFe(OH)x-2 and Pt for efficient and stable overall water splitting

Hydrogen energy represents a promising, sustainable and clean energy resource. However, widespread application of water electrolysis for hydrogen production remains limited by the reliance on expensive noble-metal-based catalysts. Developing cost-effective and efficient electrocatalysts is therefore crucial. Herein, we propose a novel heterostructure strategy to prepare non-noble-metal-based catalysts for overall water splitting. Through a simple two-step synthesis, NiTe-supported catalysts were fabricated: NF/NiTe/NiFe(OH) x -2 for the oxygen evolution reaction (OER) and NF/NiTe/Pt for the hydrogen evolution reaction (HER). Electrochemical measurements revealed outstanding catalytic activities: the optimized catalysts achieved current densities of 10 mA cm −2 at low overpotentials of 264 mV for the OER and 30 mV for the HER. When integrated into a two-electrode electrolyzer, the system required only 1.55 V to reach 10 mA cm −2 and 1.73 V to reach 100 mA cm −2 , while maintaining stable operation for 100 h and 50 h, respectively. Density functional theory calculations reveal that the Pt/NiTe heterostructure possesses a near-optimal Gibbs free energy for hydrogen adsorption (ΔG H* =-0.06 eV), which substantially accelerates HER kinetics. This work provides fundamental insights into heterostructure design and offers guidance for the rational development of efficient nanomaterials for catalytic applications.